downton



(No Model.)

R. L. DOWNTON.

DUST GOLLEGTOR.

Patented Au UNITED STATES PATENT OFFICE.

ROBERT L. DOVNTON, OF ST. LOUIS, MISSOURI, ASSIGNOR OE4 `ONE-HALF TO JAMES W. S. DOVVNTON, OE SAME PLACE.

DUST-COLLECTOR.

SPECIFICATION forming part of Letters Iatent No. 409,025, dated August 13, 1889.

Application filed January 2, 1889. Serial No. 295,116. (No model.)

To all 'whom t may concern:

Be it known that I, ROBERT L. DowNToN, of the city of St. Louis, in the State of Missouri, have invented a certain new and use ful Improvement in Dust-Collectors, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification, and in which- Figure I is a vertical section through. my improved dust -collecton Fig. II is an enlarged detail view illustrating the manner of adjusting the brushes. Fig. III is an enlarged se'ction taken on line III III, Fig. I. Fig. IV is a similar view taken on line IV IV, Fig. I. Fig. V is an enlarged detail sectional View of the connection between the dead-air chamber and delivery-flue and adjacent parts. Fig. VI is a transverse section taken on line VI VI, Fig. I. Fig. VII is a detail side elevation of the lower end of the machine.

My invention relates to a device intended more particularly for use in connection with iiour and other mills for arresting and collecting their dust; and my invention consists in features of novelty hereinafter fully de-Y scribed, and pointed out in the claims.

I nd that a large amount of fine dust that escapes the iirst settling action adheres to the wall of the vent-flue, and though a portion of this iine dust and iour is saved by the action of the incased brush or scraper shown in my application filed May 17 1888, Serial No. 274,137, still there is considerable of it that flows out with the current of airand is wasted. My object, therefore, is to provide means for saving this material.

Referring to the drawings, 1 represents an outer casing, the upper part 15 of which is preferably of the same size from top to bottom and the lower part of which is preferably tapering or smaller at its lower end than at its upper end. The part 1% of this casing is provided with a tangential opening 2, through which the dust-laden air enters.

3 represents an inner casing, the upper part 4 of which is preferably of the same size from end to end, and the lower pari of which is tapering or smaller at its lower end than at its upper end, and this lower part has perfora- `tions 30, as shown in the drawings. This inner cylinder is smaller than vthe outer cylinder, forming an intervening chamber 5. The inner casing 3 4, Iterm a vent-line. Inside of the wall or part 4 of the vent-Hue is a screen or sieve 6, which, being smaller than the part 4 of the flue, forms a dead-air chamber 7.

8 represents a central shaft having bearing on a cross -piece 9 at its upper end and a cross-piece 10 at its lower end. On the upper portion of this shaft are arms 11, to the outer ends of which are secured brushes or wipers 12. Each brush is inclosed by a housing or casing 13, as shown in Fig. III. The brushes bear or rub against the inner surface of the screen 6 as the shaft 8 revolves. The brushes may be adjusted to bring the desired pressure against the screen at all times by means of set-screws 14, working in the backs of the housings or casings 13 and jamming against dovetailed blocks 15, that carry the brushes and that slide in the horizontal ends 16 of the housing. Upon the shaft 8 are arms 17, which extend into the dead-air chamber 7, and on their ends are scraper-s 18.

19 represents a tube or delivery-Hue connecting with the dead-air chamber at 20.

21 represents vertical rods or arms located in the dead-air chamber and secured to and carried by the arms 17 or Scrapers 18.

100 represents a troughfor-ming the bottom of the dead-air chamber, upon the inner edge of which the arms 17 bear. To form a joint here that will exclude the air, I place a circular shield or ring 101 on the arms 17 that eX- tends above the bottom of the screen 6 and beneath the top inner edge of the trough, thus forming a lap-joint.

At the lower end of the machine a cone or cylinder 22 is located, and which is held concentricalLy within the cylinder by means of brackets or fastenings 23, by which it is secured to the cylinder. On the lower end of the shaft 8 may be secured a delivery-screw or conveyer 24, and beneath this are arranged one or more pairs of valves 25. I have shown two pairs. Each pair is pivoted at 2G to the lower end of the casing, and each valve is provided with a counter-weight 27, which hold IOC the valves closed, as shown in Fig. I. As the flour and dust collect in the upper pair of valves, it finally (owing to its weight) opens the valves and iiows through to the n ext pair. Before the lower pair opens the first pair has closed, thus insuring against the slightest influx of air.

The operation of my improved lnachine is as follows: The dust and air enter the chamber 5 through the opening 2, and the air cscapes through the vent-iiue 3 l, passing through the perforations 3 The iiour or dust that is contained in the air as it escapes through the vent-flue settles on the inner surface of the screen U for the following reason: The discharge-air in the ventnfiue does not fill the whole area, but escapes in a ring about three inches thick on the outside edge of the air-flue, and the air rotates in a spiral whirl, ascending up with a centrifugal action, so that the dust that gets into this vent-1lue is thrown to the outside edge of this ring of air, and of course is impinged on the surface of the wire sieve, and is forced through to the inside of the space between the imperforate and perforate wall of the vent-flue, where the air speed is reduceed so that it is easier for t-he flour and dust to fall down into the trough than it is for it to escape at the top of the vent-fine, The revolving brushes or wipers force it through the meshes of the screen into the dead-air chamber 7, where, there being no current of air, it settles, and is deposited by the scraper S into the Hue 1),which delivers it to the center of the machine, from whence it falls into the valves By incasing the brushes the immediate surface being rubbed by them is protected from the action of the escaping air, and the flour or dust is prevented from being carried out by the air-current and is forced by the brushes into the dead-air chamber. By the use of the cone or cylinder 22 a slower flow of air around the outer cylinder is produced, so that the .flour and dust will settle more readily than when the outer surface is exposed to the full velocity of the air-current. The brushes l2 are rotary-that is, they are mounted on central pins or journals 50, in which they turn as the shaft revolves-and by making the brushes so as to turn on their supports, as well as to revolve as a whole with the shaft, they are less liable to become clogged by the flour and better serve the purpose of forcing the flour through the mesh of the screen.

It is possible that in some instances the brushes might be dispensed with and the aircurrent reliedlupon to force the tlour or dust through the screen into the dead-air chamber; and, believing that I am the first to construct a machine having a dead-air chamber in connection with a centrifugal dustpcollector, I do not wish to be confined to the use of brushes in combination with the chamber.

I claim as my invention 1. In a centrifugal dust-collector, in combination with an outer casing having a tangential inlet, a screen and wall forming a dead-air chamber, against which the flour or dust is deposited under the action created by the inlet being tangential, substantially as set forth.

2. In a centrifugal dust-collector, in combination with an outer casing having a tangential inlet, a screen and wall forming a dead-air chamber, against which the flour or dust is deposited under the action created by the inlet. being tangential, and brushes for forcing the flour or dust into the dead-air chamber, substantially as set forth.

In a dustcollector, in combination with an outer casing having a tangential inlet, a screen and wall forming a dead-air chamber against which the flour or dust is deposited under the act-ion, created by the inlet being tangential, and brushes rotating on their axes bearing against the inner face of the deadair chamber and forcing the material through the meshes, substantially as set forth.

fl. In a dust-collector, the combination of an outer casing having a tangential inlet, a wall and screen forming a dead-air chamber, a central shaft, and incased brushes on the shaft bearing against the screen and forcing the material through the meshes, substantially as set forth.

5. In a centrifugal dust-collector, the combination, with the concentric outer casing, a wall and a screen forming a dead-air chamber in the outer part of the machine, of a central shaft and adjustable brushes carried by the shaft and moving over said perforated wall, said outer casing having a tangential inlet, substantially as set forth.

G. In a centrifugal dust-collector, the combination of an outer casing provided with an inlet and with an outlet for purified air, a wall and screen forming an annular dead-air chamA ber located in the upper part of said casing and surrounding said air-outlet, a trough forming the bottom of the dead-air chamber, a delivery-spout and scrapers, said casing having a tangential inlet, whereby the dust is separated from the air and passes through said screen, substantially as set forth.

7. In a dust-collector, the combination of an outer casing having a tangential inlet and an outlet, an inner casi ng forming a vent-flue, and brushes, the lower end of said vent-ilue being perforated and the upper end hayinga wall and screen forming a dead-air chamber, substantially as set forth.

S. In a dust-collector, the combination of an outer casing having a tangential inlet and an outlet, an inner casin g forming a vent-ilue, and incased brushes, the lower end of said flue being perforated and the upper end having a wall and screen forming a dead-air chamber, substantially as set forth.

9. In a centrifugal dust-collector, the com bination, with an outer casing having a tangential inlet, an inner casing forming avent iiue, and a screen forming an annular deadair chamber surrounding said I'iue, a trough IOO IIO

forming the bottom of the dead-air chamber, a deliveryspout, and scrapers, substantially as set forth.

10. In a centrifugal dustoollector, the Combination of an outer easing having a tan gential inlet, an inner casing forming a Vent-flue, a screen forming, in connection with said inner easing, an annular dead-air chamber, a trough forming the bottom of the dead-air chamber, a delivery-spout, a shaft, arms on the shaft, and sorapers on the arms, substantially as set forth.

ll. In a centrifugal dust-collector, the combination of an outer cylinder having a tangential inlet, an inner easing forming a Ventflue, a screen forming in Connection therewith a dead -air Chamber, a trough forming the bottom of the dead-air chamber, a delivery-spout, Scrapers, and arms 21, for the purpose specified, substantially as set forth.

12. In a Centrifugal dust-Collector, the Colnbination of an outer easing having a tangential inlet, an inner casing forming a Vent-flue, a wall and screen forming a dead-air chamber, a trough forming the bottom of the deadair'ohainber, a central shaft, arms on the shaft, Scrapers on the arms, and a shield lOl, substantially as set forth.

13. In a dust-collector, the Combination of an outer easing having a tangential inlet, an inner casing forming a Vent-flue, a screen forming, in connection With said inner casing, a dead-air chamber, ineased cleaning-brushes, and means for adj Listing the brushes, consisting of dovet-ailed blocks and set-screws, substantially as set forth.

14. In a dust-eollector, the combination of the outer easing having a tangential inlet, an inner easing forming a vent-flue, a screen forming, in connection With said inner casing, a dead-air chamber for catching the dust, and rotary brushes 12, having suitable journals and arranged Within the vent-Hue, substantially as set forth.

' ROBERT L. DO\VNTON.

In presence of- GEO. H. KNIGHT, EDW. S. KNIGHT. 

